487
PUBLIC RECORD OFFICE
Reference :-
C.O. 885
PUBLIC RECORD OFFICE, LONDON
ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC-
COPYRIGHT PHOTOGRAPH-NOT TO
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as is now done. Beds, mattresses, blankets, clothes, and indeed everything can be disinfected in the house, and there will be no necessity to take them through the streets to a disinfecting station. Precautionary and preventive measures, having for their object the destruction of rats in dwellings, warehouses and sewers, can be carried on with this apparatus even during the seasons when there is no plague prevailing, with the additional advantage that not only are the rats and other vermin thus destroyed, but the germs of the disease, if there are any, are also killed.
20. Gas effective for the prevention of other diseases than plague.-As this memorandum is written more with reference to the prevention of plague than any other disease, there is no need to dwell on the important uses to which the apparatus can be put in disinfecting houses infected with cholera and typhoid fever, and in preventive measures on board ship and in houses against malaria and yellow fever, both of which are spread by the mosquito, and which this gas destroys. There are probably other infectious diseases the infection of which is destroyed by the gas, but this must remain a matter for future experiment.
Among many experiments I would suggest that animals with ticks should be placed in a chamber or other receptacle with only their heads exposed to the open It may be found that the air and their bodies subjected to the action of the gas. gas would destroy the ticks on the animals without affecting the animals themselves. If successful its uses are obvious for animal diseases spread by ticks, and for the disinfection of stables and cowsheds.
Apart from the infectious diseases, the apparatus has been found to be useful in buildings infested with white ants.
June 29, 1903.
24219
II.
W. J. SIMPSON, M.D., F.R.C.P.
LOCAL GOVERNMENT BOARD to COLONIAL OFFICE.
(Extract.)
Local Government Board, Whitehall, S.W., June 30, 1903. MM. Proust and Faivre refer to certain experiments conducted at Dunkirk with the view of ascertaining the degree of efficiency of the Clayton process as a rat- destroying agency, and the effect of the process upon various kinds of goods. They found that in five out of seven vessels with cargo on board, complete destruction of rats was not secured, in one of the remaining cases one dead rat was found, while in the other no rats, dead or alive, were found after the experiment. This want of success MM. Proust and Faivre attribute to insufficient duration of the experiments. From experiments (also of brief duration) as to the influence of the process upon merchandise, it appeared that coloured woollen, cotton and silk goods almost always became to some extent bleached or discoloured in the presence of humidity, while, in one instance, there was slight bleaching of a dry sample of coloured silk. Foods acquired a strong odour of sulphur, generally, however, of short duration; and beef and cheese underwent partial discolouration. Vegetables, such as potatoes and turnips, into whose composition a large quantity of water enters, absorbed a con- siderable quantity of sulphurous acid. Water and wine exposed to the fumes both acquired a strong flavour of sulphur. Wood, painted pale pink, became slightly darker; steel, copper and nickel became slightly tarnished, a condition, however, which was removed by rubbing.
From the foregoing it will be seen that as applied in France, the Clayton process has not proved uniformly efficacious in destroying rats, nor wholly without injurious effect on many important articles of merchandise.
I am to add that the Board have under consideration a proposal that they should themselves undertake or superintend experiments, in this country and as regards vessels with cargo in situ, on the efficiency of the Clayton process under differing conditions of vessel and cargo for the purposes for which it is designed, and as to the cost necessarily incurred in securing the end desired.
30298
(Extract.)
SIR,
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Ill. PROFESSOR SIMPSON to COLONIAL OFFICE.
14, Gloucester Place, Portman Square, W.,
August 13, 1903. I HAVE the honour to acknowledge your letter of July 20th, number 25579/1903,* question of in which, by the direction of Mr. Chamberlain, it is pointed out that a grave importance to Colonial Governments which might consider the adoption of the Clayton apparatus is the effect of the gas used upon goods, especially textiles and fabrics which when not perfectly dry or in the presence of humidity it is alleged are seriously damaged; and in which it is further pointed out that it is not clear from my report that this allegation is incorrect. In connection with this an extract, from a letter received by the Colonial Office from the Local Government Board, is enclosed by you, drawing attention to the result of certain experiments at. Dunkirk instituted with the view of ascertaining the efficiency of the Clayton process as a rat- destroying agency, and the effect of the process upon various kinds of goods, and in which it is stated that, from the extract made from the report of Drs. Proust and Faivre, it will be seen that as applied in France, the Clayton process has not proved uniformly efficacious in destroying rats nor wholly without injurious effect on many important articles of merchandise.
2. Previous to making my report to the Colonial Office, I carefully considered the matters now referred to. I shall deal with the merchandise first, for it is obvious that, however effective a gas might be as a vermin killer and germ destroyer, much of its practical value would be lost if it at the same time damaged the goods that It was on this account that so much of my report had were exposed to its fumes. reference to the action of the gas on goods. I was thoroughly acquainted with Dr. Proust's and Faivre's report which was based on the result of the experiments and report made by Dr. Duriau, the Health Officer of Dunkirk and Mr. David, the Government Analyst. The conclusion arrived at by Dr. Proust and Faivre was that used in the way that we have suggested and with the methods of verification proposed by Professor Calmette this gas seems to us the most efficient process at our disposal for the destruction of rats and the disinfection of cargoes on board ship."
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The report is distinctly in favour of the process and establishes the non-injurious effect of the gas on textile fabrics under normal conditions of humidity.
It is correct that as a result of the experiment it was found that certain fabrics
gas
and which were purposely wetted and saturated with water, were affected by the suffered to some extent discoloration, but this particular state has no relationship to the normal or ordinary condition of merchandise "shipped in good order and con- dition."
The gas in no way affects dry goods of any sort, and if any articles but fruit show that they have been affected by the gas it is a conclusive proof that they were either shipped in bad condition or were damaged by water on board ship before the operation of disinfection was commenced.
3. In Dr. Proust's and Faivre's report Duriau and David gave not only the practical result obtained from the actual tests they had made, but Dr. Duriau went on to theorise as to the possibilities which might arise under conditions which had not been tested, stating that possibly on baled fabrics an injurious action might result from the sulphurous acid if the bales were not at once aired.
This statement has been interpreted on many occasions not as a possibility which required to be tested, but as a certainty which had been proved, and as an instance of this there appears an article in the Revue d'Hygiène of 20th February, 1903, in, which Dr. Jacques, the Sanitary Officer of Marseilles, misquotes Dr. Duriau, making him say that cotton and silk stuffs were injured by the sulphurous acid. It was only after this published misinterpretation of Dr. Duriau's views and report, that the theory of possible injury to baled goods if not at once aired was put to a practical test by Dr. Duriau and Mr. David. The result, as given in my report taken from Dr. Duriau's second report, was that the qualified reservations made in the first report were not substantiated when tested practically, that no injury was caused by the gas to baled goods, under ordinary conditions, and that his former fears were un- founded. 338 textile fabrics exposed for six days in the hold of a vessel under the identical conditions that would have existed had these fabrics formed the part of a vessel's cargo were absolutely unaffected as to either colour or texture. The samples
• Not printed.